This invention relates to a cord connector for one end of an extension cord and more particularly to a metallic contact strip preferably for molding within a cord connector for making electrical and mechanical connection to a blade of an attachment plug inserted thereinto.
In order to minimize contact resistance, firm contact over as broad an area as possible between a contact strip and the blade of an inserted attachment plug is desired.
In a contact strip disclosed in U.S. Pat. No. 3,241,096, slits through a metallic strip produce two-point contact wherein one part bears against a first side of a blade of an attachment plug and the second part bears against the second side of the blade. Two-point contact of this sort may be unstable and is not capable of applying substantial forces to the blade for low-resistance connection.
The above-referenced U.S. patent also discloses a contact strip providing 3-point contact with a blade of an attachment plug. However, this embodiment requires additional length in the attachment plug.
Three-point contact is also disclosed in a cord connector of U.S. Pat. No. 3,439,315. However, the three metallic strips which form each three-point contact are of unequal width and strength and thereby fail to take full advantage of the strength of the material for maximum force application to the blade of an inserted contact plug.